Dark in black sables for me are two different variables, pigment depth (the brown), and black coverage and intensity of the guard hairs.  I have done allot of research on black sables, posted and commented on this board, but to keep a long story short, heres the nuts and bolts of it.

The only way to ensure very dark black sable progeny is to use one sable (with or without black recessive)from well pigmented black recessive sable parents, and one solid black (from two well pigmented black recessive sables, keeps things simple.  Unless you have the photos and the time to trace every black to make sure none of the parents had poor pigment, good luck.).  A gene for week pigment (silver, grey etc) can travel through black lines easily. 

Length of hair is a factor as well.  Seems the longer the hair, the more the black appears to dominate visually.  Something to do with the bands of color on a single strand of hair.  Very short haired dogs usually seem to have less black.  The same dog with seasonal coat changes sometimes appear to have less black in the summer.   So another method could be to breed one dog free of longhair, to a longhair, to get stock plush coats .  Did i just say that out loud?  Genetically it would work.

One last thing to consider are unknown facial patterns that are still not yet understood genetically.  I gather you want that raccoon look dominated by black.  Make sure all the dogs have or come from dogs that had that facial pattern.  Some will say that is merely recessive black over sable, but there are a variety of recessive black facial patterns. 

Color of course should not be primary, or even secondary when breeding working dogs....However...lol with modern technology (access to photos all over the world), availablilty of so many stud dogs, why not try for your own version of perfection?  The tools are available to do so.  The people that will come forward and foam at the mouth regarding color and working dogs are the ones that have invested 20 years and allot of money in ugly dogs.  <--- hehe    

Unless every sable dog in the pedigree looks like this, you really have no guarantees.  Hopefully I helped provide the most likely set of variables to produce it.




 

Facebook friend.  Browsed those photos many times.  Also somewhat validates my analysis on black recessive genetics.  Beautiful dog.